1. Technical Field
The present invention relates to a customer premises optical network unit (ONU) and an optical transmission system. More specifically, it relates to the ONU comprising a multi source agreement (MSA) interface module or an original interface module connected with a terminal at the customer premises side, and to the optical transmission system comprising the ONU.
2. Background Art
Regarding an optical network, such as a fiber to the home (FTTH), a cable television (CATV), and the like, as reported in the below described patent document 1, an optical transmission system of passive optical network (PON) type is used, in which an optical transmission path to be connected with a central office is split by a passive splitter and then constructed for a plurality of customer premises. Such optical transmission system is called as a passive double star (PDS) as well.
Regarding such the optical transmission system, as shown in FIG. 8, for an optical fiber 102 for a user side extended from an optical line termination (OLT) 101 at the central office, a splitter 103 is connected therewith. Moreover, for a plurality of optical transmission path split by the splitter 103, via optical fibers 104-1 to 104-n, optical network units (ONU) 105-1 to 105-n in the customer premises are connected therewith.
Moreover, the ONU 105-1 to 105-n is, as shown in FIG. 9, comprised of an optical transceiver part 106 and an ONU function part 107, and then it is installed indoors. Furthermore, for the optical transceiver part 106, for example, the optical fiber 102 is connected therewith, which is led into the indoors from outdoor, via an optical splice unit 108.
Moreover, in the ONU function part 107, regarding an Ethernet (the registered trade name) interface 107a of such as 100/1000 BASE-TX, for example, a local area network (LAN) cable 110 is to be connected therewith. And then for the LAN cable 110, such as a computer 111, a router 112, a switching hub 113, and the like, are to be connected therewith. Furthermore, for the router 112 and the switching hub 113, a peripheral device 114, such as a computer, a printer, or the like, is to be connected therewith.
Moreover, the Ethernet interface 107a is comprised of a physical layer (PHY) to be connected with a media independent interface (MII) of a large scale integration (LSI) for ONU, and of a transfer and then a connector to be connected in order therewith.
[Patent Document 1] Japanese Patent Application Publication No. H09-214541